The U.S. space agency says an engineer at its Jet Propulsion Laboratory will narrate a two-hour TV documentary exploring the possibility of alien life.

Gentry Lee, a chief engineer for JPL's solar system missions, will narrate the Discovery Channel documentary that looks at the possibility of alien life from a scientific perspective, including the factors that would be necessary to produce life elsewhere in our galaxy.

NASA said Lee was chief engineer for the Galileo spacecraft project from 1977 to 1988 and, after working in a variety of positions on the Viking project from 1968 to 1976, was director of science analysis and mission planning for Viking operations.

In his current position, Lee is responsible for the engineering integrity of all the robotic planetary missions managed by JPL.

The program airs Thursday at 9 p.m. and Friday at midnight (EDT and PDT).